Portable radio receiver



April l, T952 T. H. KINMAN ET AL PORTABLE RADIO RECEIVER Filed April 1s, 1948 Patented Apr. l, 1952 PORTABLE RADIO RECEIVER Thomas H. Kinman, Robert G. Hibberd, and Cyril Hayward, Rugby, England, assignors to General Electric Company, a corporation of New York Application April 13, 1948, Serial No. 20,746 In Great Britain April 24, 1947 2 Claims.

This invention relates to radio receivers of small size capable of being carried, thus being available for use at any time and in any position, providing the available signal strength is satisfactory. The primary object of this invention is to provide a portable or pocket size radio receiver with a built-in loop antenna of novel construction.

One of the features of the invention is the provision of a carrying handle for a portable or pocket size radio receiver in which is located a built in loop antenna. An audio reproducing device, such as an earphone, is located in the case which encloses the circuits of the receiver and is connected to those circuits by means of a retractable lead so that the device may be withdrawn from the case for use and readily returned .which Fig. l is a front elevation view, partly in section, of a pocket type radio receiver suitably embodying our invention; Fig. 2 is a vertical side view, partly in section, of the receiver of Fig. l; and Fig. 3 is a sectional view of the receiver of Fig. l taken along the line 3-3.

Referring to Fig. l, we have illustrated a pocket type radio receiver constructed in accordance with our invention and which comprises a hollow outer casing I which may be formed, for example, of metal and to which is connected a rigid carrying handle 2 forming an upper extension of the casing I and incorporating therein a loop type receiving antenna 3. In order that the antenna may pick up radio waves, it is of course necessary for the handle 2 to be formed of a suitable insulating material, preferably of the molded type. As seen in Fig. 2, it is thus preferably in the form of two aperturcd insulating members 1i, 5 adapted to iit together with the apertures in alignment to provide the carrying handle. The handle is thus split into two parts. One or both parts of the handle may contain a slot 6 running around the aperture and adapted to receive the turns of wire constituting the receiving loop antenna 3, the ends of the antenna being brought through suitable bores (not shown) in the handle to extend into the casing I containing thereceiving apparatus.

Preferably the casing I is of ilat, rectangular form and made of metal, the handle portion being inserted into the upper end of the casing and secured thereto, for example, by screws (not shown). Also, the cross-section of the portion of the handle to which the casing is connected is approximately the same as that of the casing so that the handle and casing together provide a smooth external surface.

The casing I may be divided into two compartments, compartment 'I being remote from the handle and containing the batteries (not shown) necessary for operation of the receiving apparatus, while the receiving apparatusitself is contained in the upper compartment 8 which adjoins the handle. The lower portion. I ofA the casing may be hinged, as at 9, to provide ready access to the interior of the casing forattention or replacement of the batteries located therein.

Conveniently, in the neighborhood of the junction between the handle 2 and the casing I, the handle is provided with recesses I0, I I (best seen in Fig. 3) located at opposite ends of the longer of the transverse dimensions of the handle. In the recess I0 is located a knob I2 which is connected with the tuning apparatus of the receiver, the knob thus being in a convenient position with regard to the handle for operation by the user for tuning purposes. The recess II, which may be of substantially the same dimensioiiu as that of the recess IIJ is adapted to receive an audio frequency reproducing device which is illustrated as a miniature earpiece I3 connected with the output of the receiver. The device |13 is provided with an earplug I4 and an enlarged portion I5 which, when in position in the recess II, is adapted to engage the actuator I6 of a switch Il used for connecting the receiver circuits to the battery. In operation, withdrawal or insertion of the earpiece I3 actuates the switch I1 to complete or disconnect the battery circuit, respectively.

A cable I8 comprising twin flexible conductors has one end connected to earpiece I3 and is preferably arranged on a rotatable drum I9 located within the casing I and spring biased by a centrally positioned spring 20 so that, when the receiver is not in use, the cable I8 may be Wound up on the drum when the earpiece I3 is inserted into its recess II The construction of drum I9 is best seen by reference to Fig. 2 and comprises two parallel disks spaced apart by a small axial distance and arranged in the compartment 8 adjacent one of the inner faces of the casing I. One terminal of the cable I8 is connected to a contact ring 2I, While the other terminal is connected to the plate 22 of the drum I9. Contact 2I is carried upon an insulating block 23 positioned between the spring 20 and the Wound cable I8.

Contact ring 2| and plate 22 are arranged to be engaged, respectively, by spring fingers 24, 25, both of which are carried on a plate 26 formed of insulating material and biased into engagement withV ring 2I and contact plate 22 by means of a spring Z'I. The fingers 24, 25 are connected, respectively, to the output terminals of the receiver circuits (not shown). Spring biased contact plate 26 and fingers 24, 25 form a brake for the spring biased drum I9. The brake may be released by means of a push button 28 which depresses one end of a pivoted lever arm 29, the other end of arm 29 being arranged to engage a U`shaped member 30 connected to plate 26 and raise the plate and finger assembly. When the push button 28 is depressed, spring 20 causes rotation of drum I9 to Wind the cable I8 on the drum. The cable may bei unwound from the drum by merely drawing outwardly thereon.

One of theadvantages of our portable or pocket type radio receiver construction is that it permits the use of an adequate antenna compactly arranged in a convenient carrying handle for the receiver. Another advantage is the arrangement of the earpiece I3 to control the operation of the receiver circuits and the connection of that earpiece to the receiver circuit by means of a cable which is wound upon a spring biased drum so that, When the receiver is not in use, the cable I8 is conveniently stored Within the receiver casing. v

While we have shown a particular embodiment of our invention, it will of course be understood that We do not wish to be limited thereto since various modiiications may be made, and We contemplate by the appended claims to cover any such modiiications as fall within the true spirit and scope of our invention.

What We claim as new and desire to secure by Letters Patent of the United States is:

1. In a portable radio receiver comprising radio-chassis and sound-reproducing elements, a casing constructed and arranged to enclose and support said elements, a carrying handle of insulating material having a` generally U-shaped portion adapted to be grasped by the hand and a transverse base portion bridging said U-shaped portion, means securing said base portion rigidly to said casing, means deiining a circumferentially-complete channel through said portions, a loopantenna located within said channel, and electrical connections between said antenna and said chassis.

2. In a portable radio receiver comprising radio-chassis and sound-reproducing elements, a substantially rectangular casing constructed and arranged to enclose and support said elements, a rigid carrying handle of insulating material, said handle having a generally U-shaped portion adapted to be grasped by the hand and a transverse base portion bridging said U-shaped portion, attachment means for securing said base portion rigidly to one end of said casingysaid base portion having substantially the same boundary dimensions as said end of said casing and being arranged to abut against said end so as to form a smooth continuation of the adjoining walls of said casing, means securing said base portion rigidly to said face, means defining a circumferentially-complete channel through said portions of said handle, and a loop antenna having a plurality of turns disposed in said channel, said antenna being operatively connected to said chassis through said base portion.

THOMAS H. KINMAN. ROBERT G. HIBBERD. CYRIL HAYWARD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Dockendorff Apr. 4, 1950 

